Here’s some advice for Mitt Romney as he begins his general-election campaign against Barack Obama. Move quickly to the political center. No, fire up the conservative base! Talk more about your agenda. Or consider talking more about yourself. Loosen up. Maybe stick to the teleprompter. Court the right-wing media. Actually, schmooze with the mainstream media.Own your Mormonism. On second thought, conceal your Mormonism. Shake that Etch A Sketch on immigration. Then again, you need to be consistent, not a flip flopper. You cannot win without Marco Rubio. Unless maybe you can’t pick Rubio. And try dressing more casually. But, come on, don’t calculate your wardrobe, dude!

It’s enough to drive someone crazy. And according to people who have run presidential campaigns, it does. They call the daily torrent of advice, critiques, pointers and pleadings a defining element of campaign life. And they say most of it goes ignored. “It’s a massive cacophony of sounds and noise coming at you when you’re in a senior position in the campaign, from the network news to the newspapers, radio, cable, all the commentators, the high-end donors to the friends and family of the candidate,” says Steve Schmidt, who managed John McCain’s 2008 run. “And it’s important to have the discipline and focus to manage the information flow to sort out what’s important and what’s not.”

“It’s maybe the hardest thing, kibizting, for any manager to handle. And that’s infinitely more true on a presidential [campaign],” says Jim Jordan, who managed John Kerry’s 2004 campaign prior to a split with the candidate.

Mostly, say the pros, outside advice just isn’t worth much to them. When a columnist writes an open memo, or a millionaire donor whispers in the candidate’s ear at a $32,000-a-head dinner, that advice isn’t backed up by things like polling or the candidate’s long-term strategic plan. Often it will cover ground already well trod during internal strategy sessions (or on a cable-TV show, for that matter) and rejected for a specific reason. “It’s just an odd profession in that anyone who’s successful in any field, or anyone with a blog, thinks they can run a presidential campaign [better] than the guys who actually have decades of experience in politics,” says Jordan.

That’s why campaigns rarely pluck ideas from the outside din. “There’s some nuggets out there,” Scott Reed, manager of Bob Dole’s 1996 campaign, insists. But when I ask if he can recall incorporating a specific suggestion from a pundit or donor or other distant-but-well-meaning ally, he draws a blank. “Normally the things you hear on TV are, ‘The campaign needs to be bold.’ And it’s like, ‘Well, define bold for me and tell me how to implement that,” Reed says, chuckling.

Reed says it’s important that a campaign demonstrate a listening ear. But that comes at a cost: wasting time on the phone with donors and other chatty VIPs, for instance, or burning minutes being distracted by TV talking heads — whose free advice campaigns seem to resent and obsess over in equal measure. (That involves hostile criticism as well as friendly advice, by the way. At one point in the HBO movie Game Change, Schmidt admonishes a downcast McCain to “stop watching Olbermann.”)

Jordan says the real issue isn’t how campaign staff members react to a daily dose of conflicting opinions but how their boss does. “In truth, it’s mostly up to the candidate,” says Jordan. “Does he trust his staff and his professional team, or friends and family and random rich guys?” Sometimes an intervention is called for. Jordan doesn’t mention this, but Kerry’s staff allegedly took away his cell phone (not once but twice!) to prevent him from talking to people outside the campaign structure. With his corporate background and organizational fastidiousness, Romney could prove more disciplined and less susceptible to herky-jerky strategy shifts; his primary campaign, though it had its rough spots, was fairly steady and consistent.

Schmidt says the outsiders who matter are rarely heard by the rabble. “As a general proposition, you tend to pay the closest attention to people who offer advice discreetly and confidentially,” he says. In politics, though, you sometimes have to treat people you intend to ignore like they’re clairvoyants. “Kibitzing is just part of the deal, and how you balance professionalism against keeping donors and elites happy matters an awful lot,” Jordan says. Maintaining your sanity is another matter. Good luck, Mitt. And by the way: Have you considered wearing more earth tones?